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Full text of "The Cambridge Natural History"

NESOPITH&CWS* AN INTERMEDIATE FORM            553

which have been considered; for it lias the typical Sutherian
dentition of four preniolars and three molars. These teeth,
especially the superior molars, are particularly compared to the
corresponding teeth of Lemur and Galago. Of this and the
allied genus, Protochriacus, several species are known.
Adapis, a representative of another family, is one of the best
known of ancient Lemuroids. It has the typical mammalian
dentition of forty-four teeth in a close series without diastemata.
The orbits are completely separated from the temporal cavity,
the eyes looking forwards. The canines are large and caniniform.
The skull is deeply ridged behind with the usual sagittal crest.
This genus is European, and corresponds to the already mentioned
American Eocene ToinitJieriuimi perhaps belonging to the same
family.
N^esopithecus is an extinct genus from Madagascar, lately de-
scribed by Dr. Forsyth Major.1 There are two species, JVI roberti,
and JST. australis. The dental formula is I 2, O la Pm 3, M 3, for
the upper jaw, the lower jaw having but a single pair of incisors.
The lachrymal foramen is just inside, or on the edge, of the orbit,
so that one distinctive Lemurine character is lost. The genus is
also Ape-like in the form of the canines and incisors, these
having been especially compared by Dr. Ľorsyth Major with
those of the Cercopithecidae. The molars, too, agree with those
of the same family. There is, however, one important feature in
which JVesopitJiecus resembles not only the Lemurs as opposed to
the Apes, but the Malagasy Lemurs. As already mentioned (p. 544),
Dr. Major has shown that in the Malagasy Lemurs, even including
the aberrant Chiromys, and in the Tertiary and European Adapis>
the bulla tympaiii is not produced by an ossified extension of the
annulus tympanicus, but from the adjacent periotic bone, the
annulus remaining separate and lying within the fully-formed
bulla. This feature shows conclusively that Adapis is a Lemur,
and that JWesopitheeus, originally supposed to be a Monkey, cannot
be removed from the Lemuroidea, many though its likenesses to
the higher Primates undoubtedly are. However, this feature,
combined with the fact that the orbital and temporal cavities are
in communication, shows the Lemuroid position of Wesopithecus,
though it is quite conceivable that it is on the way to become
an Ape.
1 Proc. Zool. Soc. 1899, p. 987.